389983505 has 8 divisors (see below), whose sum is σ = 470566824. Its totient is φ = 310262400.

The previous prime is 389983481. The next prime is 389983507. The reversal of 389983505 is 505389983.

It is a Cunningham number, because it is equal to 19748²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 1 + 389983504 = 1^2 + 19748^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 389983505 - 2⁸ = 389983249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (389983507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 214556 + ... + 216365.

It is an arithmetic number, because the mean of its divisors is an integer number (58820853).

Almost surely, 2^389983505 is an apocalyptic number.

It is an amenable number.

389983505 is a deficient number, since it is larger than the sum of its proper divisors (80583319).

389983505 is a wasteful number, since it uses less digits than its factorization.

389983505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431107.

The product of its (nonzero) digits is 1166400, while the sum is 50.

The square root of 389983505 is about 19748.0000253190. Note that the first 4 decimals coincide. The cubic root of 389983505 is about 730.6040568475.

The spelling of 389983505 in words is "three hundred eighty-nine million, nine hundred eighty-three thousand, five hundred five".